C.1 UCUM syntax reference

Type Language / syntactical evaluation of unit expressions
Coverage Unlimited / is able to express any imaginable unit of measure
Hosted by Regenstrief Institute
Homepage https://ucum.org

UCUM (Unified Code for Units of Measure) can represent any unit used in science, engineering a business for electronic communication. It provides a single coding system for units that is complete, free of all ambiguities, and that assigns to each defined unit a concise semantics.

UCUM makes use of atomic expressions representing well known base units and a syntax used to combine these atoms to more complex units if needed.

The SI/ISQ as well as other unit systems system allows an unlimited number of possible unit expressions for a single unit. UCUM is able to clearly identify a unit no matter what unit expression is used for it.

UCUM is a recognized standard in a wide field of applications and is recommended or incorporated by other standards for example the medical field (HL7, DICOM, ISO 11240), or geosciences (WMS, GML)

UCUM defines